Prosthetic arterial grafts have been available to the medical profession for thirty years or more. However, during that thirty years the development of such grafts have been limited to those formed of textile fabrics and of semi-rigid plastics such as Teflon which have been made somewhat flexible by distension or stretching so that microscopic pores are produced which, although too small to permit the passage of blood, do permit some degree of flexibility. Such porosity does allow such grafts to eventually leak under certain conditions. Textile arterial grafts are generally a single tubular structure. Arterial graft prostheses of stretched, semi-rigid plastics have been made of multiple parts or tubes but the resultant structure has not been homogeneous or attached so that it may be separable under normal conditions of use such as during the suturing of the graft in place.
In the development of an arterial graft prosthesis it must be recognized that the optimal prosthesis should have static and dynamic elastic moduli and pressure distension in both the radial and axial directions which closely match those for normal human arteries of the same diameter. Moreover, the wall thickness should be very close to that of the human artery and should resist kinking when bent as well as do natural arteries. The prosthesis should have uniform homogeneous physical properties fully along its length so that the surgeon may cut any length he desires. Moreover, it should be easily sutured with the same needle penetration force and suture pull through force as is required with natural arteries. The suture should not pull out nor tear to any greater extent nor with any less force than with the natural artery. The prosthesis should be impervious to blood not only along the major portion of its length but also where the customary needle holes are placed during suturing. This, particularly, has not been possible with graft prosthesis of the prior art in which leaking at suture points usually exists until a thrombus is formed. Moreover, the prosthesis should inhibit tissue growth throughout the graft structure which would result in the stiffening of the graft itself. It should be compatible with blood and tissue and should also provide attachment to external tissues for fixation and avoidance of trapped fluids inside a loose tissue capsule. The graft should remain patent and unobstructed indefinitely without any inherent clot or generation of thrombo-emboli. These objectives have not been met by the arterial graft prosthesis of the prior art.